NASHVILLE, Tenn (Reuters) – Tennessee’s electric chair would be pressed back into service for executions if the state cannot obtain drugs needed to carry out lethal injections under a bill advanced Wednesday by state lawmakers.

The Tennessee Senate voted 23-3 to advance the proposal that would bring back electrocution as the method of execution if lethal injection is deemed unconstitutional or the drugs cannot be obtained. Tennessee last used the electric chair in 2007.

The proposal follows Tennessee’s decision in September to adopt the sedative pentobarbital as a single-drug method of execution. States have found it increasingly hard to obtain drugs for executions because many pharmaceutical firms, mainly in Europe, object to their use in capital punishment.

The bill’s sponsor, Senator Ken Yager, said it “closes a loophole in current law.” A companion bill is moving through the state House of Representatives.

Richard Dieter, executive director for the Death Penalty Information Center, which tracks executions, said such a law likely would be challenged as violating the U.S. Constitution’s protections against cruel and unusual punishment.

By today’s standards, electrocution could be considered a “painful and torturous” method of execution compared to lethal injection, Dieter said.

Lethal injection is the primary execution method in all states that have capital punishment, but some states allow for electrocution, hanging, firing squad or the gas chamber as alternate methods.

Tennessee would be the first state to revert to electrocution by legal mandate rather than an option chosen by an inmate, Dieter said.

Lawmakers in Missouri and Wyoming proposed adding firing squad as an execution method earlier this year.

The Tennessee Department of Correction does not have chemicals on hand to carry out executions, but is confident it will be able to secure them when needed, spokeswoman Dorinda Carter said.

“The electric chair is fully operational,” she said when asked about the measure the legislature is considering.

(Reporting by Tim Ghianni; Editing by David Bailey and Eric Walsh)

[Image: The death chamber is seen through the steel bars from the viewing room at the federal penitentiary in Huntsville, Texas in this Sept. 29, 2010 handout. By Jenevieve Robbins/Texas Dept of Criminal Justice for Reuters.]